When preparing construction material for refined uses, it is often necessary to impart a straight longitudinal and square edge on an otherwise non-square and bowed longitudinal edge. The process of imparting a straight longitudinal and square edge onto construction material (such as raw lumber or wood) is generally referred to as “straight-lining”.
There are many devices and apparatuses that have been employed to straight-line lumber or wood boards or planks, ranging from crude and simple solutions to sophisticated machinery. However, these varied attempts collectively suffer from several drawbacks, including causing invasive damage to the material, inefficiency, complexity of use, and expense of purchasing particular machines and/or components to successfully straight-line material.
Among the simple solutions offered is U.S. Pat. No. 3,587,680 (issued to Bishop), which describes a guide means having fastening means for attaching the guide means to an unfinished wood board. The fastening means is specifically described as nails, wherein the nails are driven through the guide means and into the unfinished wood board. The guide means is aligned in a specified manner so as to create a straight-line edge along which the circular saw will cut, and thus creating the desired straight-line. However, the use of nails (or other similar means) requires that the means penetrates the unfinished board, thereby unnecessarily damaging the board. In addition, driving the individual nails requires time and effort that might be better utilized.
Another simple solution is described in U.S. Pat. No. 4,026,175 (issued to Bisey), in which an alignment bar (having a square edge) is aligned with a line that indicates a path for creating a straight-line on the board. A pencil or another utensil must be used to create such a guide line. This alignment tool is useful for straight-lining relatively short boards. Marking longer boards with pencil lines is cumbersome and subject to considerable marking error.
More recently, and as disclosed in U.S. Pat. No. 5,113,734 (issued to Mahler), a straight edge ripping guide for uneven boards is described having an elongated guide piece. The guide has a push-stop member positioned perpendicular to the guide piece, and at one end thereof, and with pin points for impaling the board therein. The guide piece travels along and abuts against the standard rip fence provided on the table saw. However, this invention also damages the board (along the end edges). The board may become dislodged from the pin points if some movement of the board is experienced. In addition, the apparatus requires precision operation by the user in following a truly linear path along the rip fence.
Another similar apparatus is found in U.S. Pat. No. 5,823,084 (issued to Ramey), which discloses a tool used for straight-lining wood comprising an elongated clamp base having a straight longitudinal edge and at least one toggle clamp assembly affixed to the base so as to clamp down and secure the board to the base, and further having an extension base and bar for attachment to the base and a toggle clamp attached to the extension base. This invention suffers from the problem of having to rely upon the user to follow a precise linear path utilizing one longitudinal edge of the base and the rip fence. This invention also requires the addition of the extension to lengthen the apparatus for longer lengths of board.